My daughter and her friends made tshirts (white shirt + black sharpie) that said "Free Hugs!" and wore them to school. The Admin wasn't too pleased, but they didn't make them change. The kids then wore them to church that night. My daughter said they collected something like 37 hugs that night. 1 was a dare from a teenage boy. Group of boys standing in a corner looking at them. One breaks away, gives my daughter a very quick squeeze, turns red, and returns to his group to uproarious laughter. And a camera phone.
Nice concept though.